In the following patent applications all filed Jun. 15, 2005 of the present applicant are disclosed and claimed techniques for monitoring single mode fibers for intrusion:
Application Ser. No. 11/152,679 entitled AN INTRUSION DETECTION SYSTEM FOR USE ON SINGLE MODE OPTICAL FIBER USING FRESNEL REFLECTIONS.
Application Ser. No. 11/152,772 entitled AN INTRUSION DETECTION SYSTEM FOR USE ON SINGLE MODE OPTICAL FIBER USING A STORAGE REGISTER FOR DATA.
Application Ser. No. 11/152,680 entitled AN INTRUSION DETECTION SYSTEM FOR USE ON SINGLE MODE OPTICAL FIBER USING A SIMPLIFIED POLARIMETER.
Application Ser. No. 11/152,663 entitled AN INTRUSION DETECTION SYSTEM FOR USE ON SINGLE MODE OPTICAL FIBER USING A COST REDUCED POLARIMETER.
Application Ser. No. 11/152,681 entitled AN INTRUSION DETECTION SYSTEM FOR USE ON SINGLE MODE OPTICAL FIBER USING A POLARIMETER.
In the following patent applications both filed May 26, 2005 of the present applicant are disclosed and claimed techniques for monitoring multi-mode fibers for intrusion:
Application Ser. No. 11/137,776 entitled AN INTRUSION DETECTION SYSTEM FOR USE ON AN OPTICAL FIBER USING A TRANSLATOR OF TRANSMITTED DATA FOR OPTIMUM MONITORING CONDITIONS.
Application Ser. No. 11/137,777 entitled AN INTRUSION DETECTION SYSTEM FOR USE ON MULTI-MODE OPTICAL FIBER USING AN OFFSET LAUNCH AND TAP COUPLER.
Reference is also made to the following application filed on the same day as this application which is application Ser. No. 11/461,661 under entitled AN INTRUSION DETECTION AND LOCATION SYSTEM FOR USE ON MULTIMODE FIBER OPTIC CABLE
The disclosures of all of the above applications are incorporated herein by reference.
Using the techniques disclosed above, in physical layer intrusion detection, one factor to be considered in protecting a multi-fiber cable is the choice of how many fiber strands to protect. On one hand, a single fiber or fiber pair will protect the cable somewhat, and at a reduced price. At the other extreme, an IDS system per fiber can be quite costly.